The present invention relates to a rear projection type image display device of a construction wherein an image on an image display element is projected on a larger scale onto a transmission type screen by means of a projection optical unit including projection lenses.
Heretofore, in connection with a rear projection type image display device (hereinafter referred to as “set” as necessary) using a pixel selection type element such as, for example, a liquid crystal panel as an image display element for image display, studies have been made for decreasing the height and depth (making the set compact) by a method different from a set using a CRT as an image display element. For example, a rear projection type image display device using a projection optical unit for projecting an image on a larger scale onto a transmission type screen obliquely is disclosed in Japanese Patent Laid-open Nos. 5-134213 (Literature 1), 2000-162544 (Literature 2) and 2002-357768 (Literature 3).